Unitized washing machine bushing

ABSTRACT

There is disclosed an improved washing machine that employs an apparatus in the form of a molded, unitized bushing mounted at the outer end of the center post to perform the functions of maintaining spatial relationships between the agitator shaft and the spin tube and between the spin tube and the center post, providing a bearing for the agitator shaft and the spin tube and sealing the drive means from penetration by the washing fluid when a lubricant is used. Provision is also made to seal portions of the bearing surfaces adjacent to the lubricant-retaining means. A method for installing the unitized bushing in existing washing machines is also disclosed.

1 1 Sept. 30, 1975 [57] ABSTRACT There is disclosed an improved washing machine that employs an apparatus in the form of a molded. unitized bushing mounted at the outer end of the center post to perform the functions of maintaining spatial relationships between the agitator shaft and the spin tube and between the spin tube and the center post. providing a bearing for the agitator shaft and the spin tube and sealing the drive means from penetration by the washing fluid when a lubricant is used. Provision is also made to seal portions of the bearing surfaces adjacent to the lubricant-retaining means. A method for installing the unitized bushing in existing washing machines is also disclosed.

United States Patent [1 1 Fahmie UNITIZED WASHING MACHINE BUSHING Inventor: Michael E. Fahmie, 440 Bella Vista.

Brick Town. NJ. 08723 June 6, 1973 [22] Filed:

Appl. No.: 367,549

[56] References Cited UNlTED STATES PATENTS 2,161,619 6/1939 Dunham 3.511.067 5/1970 Matzen 3.710.947 1/1973 Churhut...........................

PII'HHII) Eraminer-Harvcy C. Hornsby Assistant Eraminer-Philip R. Coe Attorney. Agent, or FirmSiegmar Silber. Esq.

US! Patent Sept. 30,1975

1 UNITIZED WASHING MACHINE BUSHING BACKGROUND OF THE INVENTION coact as the need may be. For example, with the com-. mon arrangement of an inner tub for receiving clothes to be washed being supported indirectly by the center post of an outer tub and directly by a spin tube within the center post and further of an agitator depending into the inner tub driven by an agitator shaft housed within the spin tube, it is accepted practice to drive the agitator and inner tub in unison and at high speed during a spin cycle so as to extract water from the inner tub and clothes therein by centrifugal force. V

Centralizing drive transmitting components at the common central exis requires efficient sealing means for excluding washing fluid from the drive transmitting components and the drive motor, efficient bearing elements for supporting rotatory and reciprocatory action common to such washing machines, and bushing means for maintaining spatial relationships among the agitator shaft, spin tube and center post. Previously, such sealing, bearing and bushing elements were incorporated into the machine at a location requiring extensive disassembly of the machine for maintenance thereof. Thus, quite frequently at the point in the useful life of the machine that sealing or bearing failure occurs, largely because of the inaccessibility of the aforementioned elements, the cost of replacement is frequently disproportionate to the anticipated value of the repaired machine. Secondly, this arrangement of the drive transmitting elements presents an unduly complex manufacturing chore.

While a number of arrangements of washing machines have been employed in the past, the vertical axis design incorporating outer and inner tubs with an agitator depending into the latter thereof has become widely used and accepted.

It is a general object of the present invention to provide an improved washing machine.

Another object is to provide a machine in which the bearing and sealing elements for the drive transmitting components can be readily replaced.

A more specific object is to provide a replacement apparatus and a replacement method to be used in conjunction therewith for use with existing drive transmitting systems.

One feature of the invention isto provide a bushing that simplifies the assembling and manufacturing of the drive transmitting system.

Another feature of the invention is to provide a unitized bushing incorporating sealing and bearing functions thereby substantially reducing the number of parts required in the drive transmitting system.

Still another feature of the invention is to provide sealing, bearing and bushing means which are readily accessible for replacement thereof.

Other objects, features and advantages will become apparent from the following description and appended claims.

SUMMARY OF THE INVENTION In carrying out the invention according to the arrangement which will be described, the sealing, bearing and bushing functions are effected by a unitized bushing structure having a plurality of passageways concentrically arranged, such bushing providing predetermined spaced relationships among the drive transmitting components, between the center post and the spin tube and between the spin tube and the agitator shaft. The unitized bushing structure has surfaces coacting with the surfaces of the center post, the spin tube and the agitator shaft for bearing and sealing thereof.

BRIEF DESCRIPTION OF THE DRAWINGS Fo a clearer understanding of the invention reference may be made to the following detailed description and the accompanying drawings, in which:

FIG. 1 is pictorial view with cutaway portions showing the application of the invention to a washing machine of the vertical axis arrangement;

FIG. 2 is a cross-sectional view of a detail of the vertical axis washing machine of FIG. 1 showing the bushing arrangement of the first embodiment;

FIG. 3 is similar to FIG. 2, but shows the arrangement of a second embodiment; and

FIGS. 4 and 5 are similar to FIG. 2, but show the arrangement of a third and a fourth embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown on the drawings:

It will be understood that the principles of the present invention are applicable to any machine wherein elements such as the agitator and the tub are driven through concentric shafts having common central longitudinal axis as in domestic and commercial laundry apparatus whether of the vertical axis arrangement or otherwise. For purposes of illustration, however, the present invention is shown as embodied in a vertical axis washing machine, shown generally in FIG. 1, it being understood that the bushing may be adapted to a horizontal axis machine.

In the embodiment of the invention illustrated in FIG. 1, there is shown an automatic washing machine designated generally at 10, having controlled washing, rinsing and spin drying cycles (the electrical controller therefor not being shown). Machine 10 has an enclosure 12 in the form of a sheet metal cabinet surrounding fixed outer tub 14 and rotatable inner tub 16 for receiving washing fluid and clothes to be washed therein in the conventional manner.

The outer tub 14 is sealed at the central lower portion thereof to a hollow center post 18 forming a suitable container for washing fluid and excluding said washing fluid from the driving mechanism 20 of the apparatus. Connecting driving mechanism 20 to inner tub 16, which is rotatably mounted within outer tub 14, is spin tube 22 joumaled within center post 18 both of which share the same central, longitudinal axis 24. Inner tub 16 has foraminous walls so that washing fluid retained by outer tub 14 is shared by inner tub 16. The apparatus is constructed so that upon emptying of tubs 14 and 16 washing fluid retained by clothes in inner tub 16 may be substantially extracted therefrom by highspeed spinning of inner tub 16 through driving mechanism 20 and spin tube 22.

For washing purposes, on central longitudinal axis 24 and within spin tube 22, agitator shaft 26 is mounted therein being connected at one end to an agitator 28 which depends into inner tub 16. Agitator shaft 26 is connected at its other end to driving mechanism 20 that during the washing cycle drives agitator 28 in a reciprocating or oscillating motion.

On the hollow center post 18 that extends upwardly from the outer tub 14 is stationary sleeve 30 which surrounds spin tube 22 and provides stabilization for inner tub 16. To prevent washing fluid from flowing between outer tub l4 and spin tube 22 and thus downward into the driving mechanism 20, a sealing means is provided. In the present invention, a bushing indicated generally at 32 is attached to spin tube 22 being rotatable therewith and journaling agitator shaft 26 within aforementioned spin tube. During the reciproacting motion of the agitator shaft 26, spin tube 22 and inner tub 16 are held stationary while the agitator 28 is structured so as to develop a washing action.

Although the principles of the present invention are applicable to any vertical axis washing machine such as one of the so-called overflow rinse type, the present embodiment shows a perforated inner tub 16 having foraminous walls with a plurality of openings therein. Thus, although the plumbing arrangements may vary from one type of washing machine to another and are not necessary to the understanding of the present invention, it will be appreciated that fluid can be pumped to and forced from outer and inner tubs 14, 16 and can be confined by outer tub 14. Additionally, for automatic sequencing the machine 10 is programmed by an electrical controller (not shown), whereby it is sequentially operated in presettable fashion through a cycle including washing, rinsing and spin drying modes.

Referring now to FIG. 2, the bushing 32 is shown in detail. The bushing as shown is a first and preferred embodiment whereby the part is a single utilized part designed to perform sealing, bushing, bearing and unitized functions. In structure although shown as a single molded part, it would be obvious to those skilled in the art to make the bushing in several components and assemble them as one. The bushing 32 is a basically frusto-conical body 34 arranged symmetrically about its longitudinal axis having a plurality of concentric passageways with the innermost one passing throughout the body 34. The innermost passageway serves as agitator shaft bearing 36 and is substantially equal in diameter to that of agitator shaft 26. Each end of the passageway forming the agitator shaft bearing portion 36 has sealing means, namely agitator shaft sealing lip 38 and agitator shaft sealing bead 40. Intermediate the two sealing means are recesses in the walls of the agitator shaft bearing portion 36 for retaining lubricant inserted therein. While shown herein as rectangular lubricant cells 41, the recesses could take any shape such as grooves for holding lubricant-retentive material. The middle or second passageway or spin tube sleeve 42 is dimensioned so as to press fit onto spin tube 22 and to be locked thereto by a first locking means 44 which coacts with corresponding second locking means in the uppermost end of spin tube 22. First and second locking means may be an internal and corresponding external set of splines.

The outermost passageway serves as the stationary sleeve bearing portions 46 and is substantially equal in diameter to that of stationary sleeve 30. Each end of the passageway forming the stationary sleeve bearing portion 46 has sealing means, namely stationary sleeve sealing bead 48 and stationary sleeve sealing lip 50. Similar lubricant cells 49 are employed with stationary sleeve bearing portion 46 as are shown heretofore as being employed with agitator shaft bearing portion 36.

Referring now to FIG. 3, the bushing 52 is shown in detail. The bushing as shown is a second embodiment wherein, while similar in concept to the previously described embodiment, the part is molded from a highimpact thermoplastic polyester resin having natural lubricity. The plurality of concentric passageways, here designated 54, 56 and 58, are respectively agitator shaft bearing portion 54, spin tube sleeve 56 and stationary sleeve bearing portion 58. In this embodiment, because of the lubricity of the material, additional lubrication fields may not be required and similarly the need for sealing beads for retention of lubricant may be eliminated. However, the structure still exhibits upper and lower sealing lips 60, 62 for sealing the drive components against washing fluid. Since the lubricant serves also to cool bushing 32, cooling of the bushing material of bushing 52 is provided by a plurality of air scoops 64 and a corresponding plurality of substantially longitudinal vents 66.

Referring now to FIG. 4, the bushing is shown in detail. The bushing as shown is a third embodiment wherein, while similar in concept to the previously described embodiments, the part is constructed from a fiber laminate material, The plurality of concentric passageways, here designated 72 and 76, are respectively agitator shaft bushing portion 72, and stationary sleeve bushing portion 76. Because of the properties of the fiber laminate, the structure is adapted to include grooves 78, for agitator shaft seals 82 and stationary sleeve seals 84 and bearing-retaining housings 86, 88 for bearing inserts, such as agitator shaft bearing insert 90 and stationary sleeve bearing insert 92.

Referring now to FIG. 5, the bushing is shown in detail. The bushing as shown is a fourth embodiment while similar in concept to the previously described embodiment, the part is constructed in a foreshortened design so that the lower portion 102 as shown on the previous embodiment is now so configured so as to abut the topmost portion of the stationary sleeve bearing 58. Such structure drastically reduces the amount of material required and the complexity of the molded bushing. Here only a vestige of the outermost passageway as shown in previous embodiments as passageway 58 remains. To improve the sealing of the fourth embodiment a gasket (not shown) may be employed between the lower lip and the aforementioned stationary sleeve bearing.

Although in the above embodiments, the bushing arrangements are provided with a structural description relating them to a particular washing machine arrangement having such functional parts as an agitator shaft and a stationary sleeve, which functional parts lend functional descriptors to the bushing sleeve and bearing portions, it will be obvious to one skilled in the art that the bushing 32, 52 or 70 may be adapted to washing machines and similar applications"havingmoncen tric drive shaft arrangements requiringbushing; sealing and bearing elements. I i

In operation bushing 32, 52, similarly and thus only the function of bushing 32 will be described as exemplary of allthe 'abovedescribedembodiments. As shown. in FIG. 2, the agitator shaft 26 and stationary sleeve 30 are provided with correspond ing bearing portions. During the initial part of the oper= ational cycle, whether'controlled manually or automatically, the outer and inner tubs'a're'filled with washing fluid and the bushing 32 is at rest-without any "of'the moving components therewithin functioningjNe'x'tthe inner tub 16, which is attached to'the bushing 32, is secured by a braking arrangement (not shown) while driving mechanism 20 causes agitator shaft 26 to be operated in a reciprocatoi'y fashion thereby produ cing a moving shaft within a substantially stationary bearing portion 36. Upon concluding the agitating or washing action, water is extracted as mentioned hereinabove. In this mode of operation commonly referred to as the spin cycle, the spin tube 22, bushing 32, and inner tub 16 all rotate at high speed producing a moving bearing portion 46 rotating about stationary sleeve 30. During the spin cycle, as agitator shaft 26 is freely journaled within its related bearing portion 36, the weight of the clothes being washed and the washing fluid carry the agitator 28 in a similar rotational manner as the inner tub 16. The rate of rotation of the agitator 28 at any given point in the spin cycle thus depends in substance upon the material in contact with the vanes of the agitator 28, the inertia of agitator 28, and the frictional forces acting upon agitator shaft 26. In the spin cycle, the bearing portion 36 supports the differential in rotational movement between. spin tube 22 and agitator shaft 26 or, in other words bearing portion 36 is subjected to no loading in the initial part of the spin cycle when the rotation is substantially at the same rate of speed and to high loading toward the end of the cycle where there is increased differential between the rates of rotation.

From the foregoing it will be appreciated that this in- -vention provides a washing machine in which an improved bushing arrangement is described. Although those skilled in the art may use the embodiments as shown which is believed to best represent the objectives and advantages of the invention other variations are contemplated as being within the scope of the invention.

I claim:

1. An improved washing machine having a tub to receive washing fluid and clothes to be washed therein, said tub having a central axis, a center post having a first longitudinal axis supporting said tub about said central axis, a spin tube having a second longitudinal axis within said center post arranged with said first and second longitudinal axes coincident, said spin tube connected to said tub for driving thereof during extraction of said washing fluid, agitating means positioned within said tub for agitation of said clothes during the washing thereof, an agitator shaft having a third longitudinal axis within said spin tube arranged with said first and third longitudinal axes coincident, said agitator shaft connected to said agitator means for driving thereof during said agitation, wherein the improvement comprises 70 and b armada:

a bushingformed so, as to provide predetermined spaced relationships between said centerpost and said-spin tube and between said spin tube and said -;.-agitato'r shaft, and k l said bushing having. surfaces v.coacting with surfaces -f' iofz said center post, said spin tube and said agitator.

shaft.' r .1

1 2: An improved washing machine asadescribed in claim' '1-wherein the improvement furthercomprises cooling means for'removing heat from said bushing} -3. Ah improved-washing machine as described -in claim 1' wherein the improvement furthercomprises a plurality of sealing means for'excluding washing fluid and foreign matter from the spaces between said spin tube and said agitator'shaft and between said center post and said spin'tube.

4; An improvedwashing-machine as described in claim 3 wherein the improvement further comprises mounting means for attaching said tub to said spin tube.

5. An improved washing machine as described in claim 4 wherein said bushing is a unitized molded part.

6. A bushing for a washing machine having a cylindrical center post, a tub to receive washing fluid and clothes to be washed therein mounted on said center post, an agitator shaft inserted longitudinally through said center post, an agitator supported by said agitator shaft depending into said tub, a spin tube surrounded by said center post for engagement with said tub being capable of transmitting drive forces to extract washing fluid from said tub, said bushing comprises a substantially frustoconical body arranged symmetrically about a first longitudinal axis normal to a base thereof, said body having a first passageway with a second longitudinal axis coincident with said first longitudinal axis, said first passageway being of a diameter substantially equal to that of said agitator shaft extending throughout said body, a second passageway with a third longitudinal axis coincident with said first longitudinal axis, said second passageway being of a greater diameter than said first passageway and extending from a first upper terminus substantially midway between an end opposite said base and said base to the base of said body, and a third passageway with a fourth longitudinal axis coincident with said first longitudinal axis being of a diameter greater than said second passageway and substantially equal to that of said center post, said third passageway extending from a second upper terminus substantially midway between said first upper terminus and said base to the base of said body,

a first shoulder at said first upper terminus of said second passageway, and

a second shoulder at said second upper terminus of said third passageway.

7. A bushing as described in claim 6 wherein cooling vents are arranged symmetrically about a peripheral area adjacent said base of said body.

8. A bushing as described in claim 7 wherein said vents are formed by holes extending substantially longitudinally along said peripheral area of said base to an outer wall of said body and having scoop-shaped air entryways at said base.

9. A bushing as described in claim 6 wherein a lip of said first passageway adjacent the end opposite said base is of a diameter slightly less than the remainder of the passageway so as to be in press fit relationship to said center post thereby sealing said shaft from washing fluid and foreign matter.

10. A bushing as described claim 9 wherein an opening in said first shoulder is of a diameter slightly less than said agitator shaft so as to be in press fit relationship therewith, for retaining lubricant between said agitator shaft and said bushing and between said opening in first shoulder and said lip of first passageway and wherein a wall of said third passageway adjacent said second shoulder and circumferentially about said third passageway is raised being of a diameter slightly less than said center post so as to be in press fit relationship therewith for retaining lubricant between said center post and said bushing.

11. A bushing as described in claim 6 wherein an outer area adjacent said end opposite said base is threaded to receive fastening means for attaching said tub to said bushing.

12. A method for rebuilding a washing machine having a cylindrical center post, a tub to receive washing fluid and clothes to be washed therein mounted on said center post, an agitator shaft inserted longitudinally through said center post, an agitator supported by said agitator shaft depending into said tub, a spin tube surrounded by said center post for engagement with said tub being capable of transmitting drive forces to extract washing fluid from said tub wherein the steps thereof comprise a. establishing the spaced relationships between said agitator shaft and said spin tube and between said spin tube and said center post by press fitting thereto an external bushing having internal concentric bearing surfaces one for each spaced element, and b. mounting said tub on the exterior wall of said external bushing thereby preventing axial movement of said bushing.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTICN Pa 5,908, +ll Dated September 50, 1975 Inventor(s) Michael E o Fahmie It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Columns 7 and 8, Claim 12 should be deleted.

should read 11 Claims Signed and Scaled this Third Day of August 1976 [SEAL] A nest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ufPatents and Trademarks 

1. An improved washing machine having a tub to receive washing fluid and clothes to be washed therein, said tub having a central axis, a center post having a first longitudinal axis supporting said tub about said central axis, a spin tube having a second longitudinal axis within said center post arranged with said first and second longitudinal axes coincident, said spin tube connected to said tub for driving thereof during extraction of said washing fluid, agitating means positioned within said tub for agitation of said clothes during the washing thereof, an agitator shaft having a third longitudinal axis within said spin tube arranged with said first and third longitudinal axes coincident, said agitator shaft connected to said agitator means for driving thereof during said agitation, wherein the improvement comprises a bushing formed so as to provide predetermined spaced relationships between said center post and said spin tube and between said spin tube and said agitator shaft, and said bushing having surfaces coacting with surfaces of said center post, said spin tube and said agitator shaft.
 2. An improved washing machine as described in claim 1 wherein the improvement further comprises cooling means for removing heat from said bushing.
 3. An improved washing machine as described in claim 1 wherein the improvement further comprises a plurality of sealing means for excluding washing fluid and foreign matter from the spaces between said spin tube and said agitator shaft and between said center post and said spin tube.
 4. An improved washing machine as described in claim 3 wherein the improvement further comprises mounting means for attaching said tub to said spin tube.
 5. An improved washing machine as described in claim 4 wherein said bushing is a unitized molded part.
 6. A bushing for a washing machine having a cylindrical center post, a tub to receive washing fluid and clothes to be washed therein mounted on said center post, an agitator shaft inserted longitudinally through said center post, an agitator supported by said agitator shaft depending into said tub, a spin tube surrounded by said center post for engagement with said tub being capable of transmitting drive forces to extract washing fluid from said tub, said bushing comprises a substantially frustoconical body arranged symmetrically about a first longitudinal axis normal to a base thereof, said body having a first passageway with a second longitudinal axis coincident with said first longitudinal axis, said first passageway being of a diameter substantially equal to that of said agitator shaft extending throughout said body, a second passageway with a third longitudinal axis coincident with said first longitudinal axis, said second passageway being of a greater diameter than said first passageway and extending from a first upper terminus substantially midway between an end opposite said base and said base to the base of said body, and a third passageWay with a fourth longitudinal axis coincident with said first longitudinal axis being of a diameter greater than said second passageway and substantially equal to that of said center post, said third passageway extending from a second upper terminus substantially midway between said first upper terminus and said base to the base of said body, a first shoulder at said first upper terminus of said second passageway, and a second shoulder at said second upper terminus of said third passageway.
 7. A bushing as described in claim 6 wherein cooling vents are arranged symmetrically about a peripheral area adjacent said base of said body.
 8. A bushing as described in claim 7 wherein said vents are formed by holes extending substantially longitudinally along said peripheral area of said base to an outer wall of said body and having scoop-shaped air entryways at said base.
 9. A bushing as described in claim 6 wherein a lip of said first passageway adjacent the end opposite said base is of a diameter slightly less than the remainder of the passageway so as to be in press fit relationship to said center post thereby sealing said shaft from washing fluid and foreign matter.
 10. A bushing as described claim 9 wherein an opening in said first shoulder is of a diameter slightly less than said agitator shaft so as to be in press fit relationship therewith, for retaining lubricant between said agitator shaft and said bushing and between said opening in first shoulder and said lip of first passageway and wherein a wall of said third passageway adjacent said second shoulder and circumferentially about said third passageway is raised being of a diameter slightly less than said center post so as to be in press fit relationship therewith for retaining lubricant between said center post and said bushing.
 11. A bushing as described in claim 6 wherein an outer area adjacent said end opposite said base is threaded to receive fastening means for attaching said tub to said bushing.
 12. A method for rebuilding a washing machine having a cylindrical center post, a tub to receive washing fluid and clothes to be washed therein mounted on said center post, an agitator shaft inserted longitudinally through said center post, an agitator supported by said agitator shaft depending into said tub, a spin tube surrounded by said center post for engagement with said tub being capable of transmitting drive forces to extract washing fluid from said tub wherein the steps thereof comprise a. establishing the spaced relationships between said agitator shaft and said spin tube and between said spin tube and said center post by press fitting thereto an external bushing having internal concentric bearing surfaces one for each spaced element, and b. mounting said tub on the exterior wall of said external bushing thereby preventing axial movement of said bushing. 